Gradual changes in your lifestyle are much easier to make than major changes all at once. For three days, write down the foods and drinks you consume at meals and as snacks - Do you have too few fruits andor portions of vegetables? To start with, try to eat just one extra piece of fruit and vegetables a day. Are your favourite foods high in fat and making you gain weight? Don't eliminate those foods and feel miserable, but try to choose low fat options or eat smaller portions. And start using the stairs at work